Sealing for electric apparatus.



PATENTED NOV. 26, 1907.

J. R.-BAKER. SEALING FOR ELECTRIC APPARATUS.

APPLICATION FILED MAR. 31, 1905.

l/q i'bmwacn UNITED STATES PATENT UFFHJE.

SEALING FOR ELECTRIC APPARATUS.

Specification of Letters Patent.

Patented Nov. 26, 1907.

Application tiled March 31,1905. Serial No. 253.100.

To all whom it may concern:

Be it loiownihat .l, Jwnns it. BAKER, a citizen of the L nited States, and resident of Arlington, count; of .llu'dson, State of New Jersey, have invented certain new and useful linprm'einents in Scalings tor Electric Apparatus, oi which the following is a specification.

My invention relates to the construction of electric Vapor apparatus, and more particularly that class in which a small quiuitity of mercury, or other heavy fluid, is contaiimd within a staled-oll' chamber.

'In the ordinary construction of vapor npparatus of the cl'iaracter referred to ditliculty is sometimes encountered in preventing the breakage ol the glass ontainer at the point where the device is sealed oll' after it has been exhausted. in sealing I ell any Vacuum 2-0 chameer, it is customary to employ a small ;.tube, which, during the, process 01' sealing, constitutes -a continuation of the chamber itsell and thereafter is sealed ell by fusing, leaving a narrow conical "point. When in shipment or otherwise, a small quantity of heavy hold, such as mercury, covers this sealing-oil point, and a slight jar is liable to break the seal open by reason of the com-entrotion upon the pointof the blow caused by the movement of the fluid.

l hev'found that by placing a small plug of gl'ass'or other suitable material in the sealing oil cavity, the seal may be protected against such blows by distributing the blow over a erger surface and preventing its concentration Within the cavity. Various dill'ere'nt means may be employed for securing the plug in the proper place.

In the accompanying drawings, Figure l 40 illustrates a completed lamp involving the features of construction; Fig. 2, represents one method of temporarily supporting the plug during'the process of exhaustion; Fig.- 3 illustrates a modification of Fig. 2; and Fig. 4

illustrates a step in the process of sealing oll'.

Referring to the figures, 1 represents a portion of the main body of a mercury vapor apparatus, and 2 represents one of the electrodes therefor. This electrode is shown as being carried by a leading-in,conductor, 3,

material located at the mouth of the sealing oll cavity. This is shown as being attached to a thin wire of platinum or other material (5. in the process of construction the plug may be inserted through the opening, 7, (see Fig. 2) to which the sealoll tube, 3, is [used The wire (3 is here shown as being ten'ipornrily fastened to the wall of the vessel at a point 9.

After the device has been exhausted the tube is sealed oil at a point beyond the. attachment of the wire. The lower contraction is then sealed. and drown outward, as shown in Fig. 4, bringing the plug into the sealing oll' cavity. This is done .while the glass is soft. The glass and wire are then severed at the point 10. The exposed end of the platinum wire may then be coated witlra drop o'l melted glass, as shown in Fig. 1.

lnstead of temporarilyfastening the wire 6 to the side of the tube, a longer wire may be used as shown in Fig. 3, a small hookbeing formed on the end. This wire is first slipped into the lamp through the large opening as in the first instance, and alter the sealoll' tube has been join-ed to the lamp, the wirc'is hooked up to the position shown in Fig. 3, by means another fine wire. The spring of the wire is sullieient to hold it in p ace during the exhausting; and the position of the plug with reference to the adjacent electrode maybe such as-to prevent its dropping into the tube.

1 have found in practice that a. seal made in this manner prevents almost entire y the breakages which were liahle to occur with a seal having a cavity unfilled.

When the lamp or other device has to be washed or otherwise treated, it is sometimes advisable not to put'in the plu and attaching wire until the lamp or other device is ready for the pump. 111 this case a. small hole Ina be blown in the, lamp or other device preierably in the .bulb, the plug inserted and the hole closed.

I claim as my invention 1. A seal for vacuum ap uretus, consisting oi a plug fitting within tie seal-oil cavity,

and means for securing the sonic in position. 2. A seal for vacuum apparatus, consisting of a rigid plug fitting wit un the seal-ell cavity, and means for securing the some in position. v

3. The combumtion with the seal-o1f prol 5 jection of an inclosing chamber forapparw 1 pamtus, consisting of a projecting portion of the wziii oi the vessei formln a conical cavity, and a piug of heat-resisting material 10- jection of an incl'osing chamber for epparatus, of a rigid body held Within the seal-oi? cavity. r

' 4. The combination with the seal-off pro ing the same in position.

1 Signed at New York, in the county of New -York, and. State of New York, this' fourteenth day of March A. Dr 1905.

JAMES R. BAKER.

tus, of a body heldwithin the seal-off cavity. 5. Thecombination iththe'lseal-ofi of Q mercury vaporappamtus, of a shock-resisti ing body. located Within the seal-off cavity, 10 and a Wire passing through the wall of the Witnesses: v

WM. H. CAPEL, l

Vessel, alnd holding the same in position.

PERGY H. THOMAS.

6. Asea-l for mercury vapor and like apcated Within the cavity, and means for hold- 

